Die-stock.



NITED STATES PATENT OFFICE.

RUSSELL B. TEWKSB''RY, OF CLEVELAND, OHIO, ASSIGNOR T0 TEE OS'IER MANUFAC- TURING GOMPANY, OF OLEVELANID, OI-IIO, A CORPORA'IION' OF OHIO.

DIE-STOCK.

T0 all wh0m z't may concem:

Be it lmown that I, RUSSELL B. TEWKS- BURY, a oitizen of the United States, residing et Cleveland, in the county of Cuyahoga end State of Ohio, have invented a certain new end useful I1nprovement in Die-Stocks, of whioh the following is a full, clear, end exact deseription.

The iniprovement in die stoeks, herein shown end desoribed, are designed to produce a strong, durable, end inexpensive tool, whieh may loe organized to out tapered threads on pipe f ditterent diameters, end to eutomatieally withdraw the dies from the work when the required length of thread has been out, end to hold them out while the die earrier end work holder are moving to their proper relative positions for beginning the thread outting operation end to automatioally return the dies to proper working positions at such time.

The invention oonsists of the eonstruotion end oombination of arts hereinafter desoriloed end pointed out definitely in the claims end shown in the aocompanying drawings in Which Figure 1 is a central longitudinal seotional view und Fig. 2 is a front end vievv of a die sto.ok embodying the invention.

The work holder l is of familiar nonstruotion, being a built up n1emloer of tubular for1n so that the pipe or other eylindri aal piece of Werk to be threaded may be passed through it, end being provided with suitable 1neans whereby it may be olamped to seid work. The die oarrier 2 is likewise tuloular end is oapalole of moving rotatively end longitudinally relative to the work holder. In the eonstruetion shown the die oarrier has its rear end externally threaded so that it may sorew into the internelly threaded work holder; wherefore as the die oarrier is turned relatively to the work holder it Will move longitudinally relative thereto et such a rate es is determined by the pitoh of the engaging threads upon these t-wo arts.

At the front end of the die carrier is an outwardly extended flange 2 which is provided With ZL plurality of pairs of forwardly projeoting lugs 2 end 2 which form radial guideways :Eor the ohasers or dies 3. In the particuler construotion shown the dies de not themselves engage direotly in these guideways, but are fixedly held in die oases Specification of Letters Patent.

Applieation fi1ed April 22, 1912.

Patented Beo. 23, 1913. Seria1No. 692,373.

4; end it is these die cases Whi0h directly engage with the guide lugs referred to. The employment of die cases is an old expedient in this art end nothing new is claimecl for it herein. In faot, it is a matter of no eonsequence to the present invention whether the dies direotly engage the guide lugs or whether they are imn1ovably held in oases which engage seid guide lugs.

Euch of the die cases l1itS two laterally projecting ribs 4 011 its side which engage in corresponding grooves in the inner faees of the guide lugs. The dies fit nicely in these oases; und their rear ends, as shown, abut against shoulders 4 near the rear ende of the cases. Gibs 4- seoured to the top Walls of the oeses overhang the dies end hold them immovable in seid cases.

5 represents a Iing Whioh is rotatively mounted upon the Werk holder, but is held ageinst longitudinal movement relatim thereto. The particular 1neans shown for preventing seid longitudinal movement without interfering with the rotative move- 1nent, include a oiroumferentiel groove lin the work holder, and one o1 more pins 5 whioh sorew through the ring and projeet into this groove.

6 represents te1nplet bare; whioh are fixed to this 1ing end extend longitudinally therefrom forward through suitable openings in the flange 2 of the die oarrier. Essentially there is one of these te1nplet bare assoeiated With eaoh die. Euch of these te1nplet bars has a guideway for engagement, direetly or indireotly With the assooiztted die. In the speoifie eonstruetion shown these several templet bars are formed integral with the ring 5. This, however, is innnaterial beeause the essential t-hing is to have the templet bars rigidly fixed to the ring while the tool is outting threads. In the eonstruction shown euch te1nplet bar is bifuroated end the assooiated die passes between the two brenohes of the bar. This, however, is also immaterial insofar es the present invention is coneerned, because only one bar whioh passes 011 one side only oit' the essooieted die is required. By bifuroating the templet bare und allowing the two branohes thereof to engage the outer faoes of the ribs 4 on the die eases the templet bars end ring are compelled to rotate With the die carrier in both direotions. Any other means, however, whioh Will compel the simulteneous rotetion of the ring with the die cerrier, but which Will permit the temple-t bers to 1nove longitudinall; relative so the die eerrier should be regerded es the equivelent 0f the pertieuler construction shown.

The so-celled guidewey With which eech templet ber is provided is en inclined groove 6" in thet feoe which is edjeoent 130 the essoeieted die cese; end e pin 4 fixed to end projecting leterelly fron1 the essooieted die cese projeots into this guide groove. I;E the die stock is to be orgenized t0 eut tepered threeds, this groove will be inclined to the exis of ehe tool et the required inclinetion.

If, in using the tool, the die cerrier loe screwed into end out of the worlr holder such distences es will elweys keep seid pin in the streight pert of seid guide groove, es shown, the dies Will loe greduelly retrected er ellowed to ret-rect, es the cese mey be, es the die cerrier is screwed into the work holder, end this will result in the cutc-ing of e tepered threed. Moreover, es the die cerrier is screwed out of t-he work holder seid dies Will be n1oved in the contrery direotion end Will essume the required position for sterting to cut e new threed when the die eerrier hes losen screwed out of the work holder fer enough.

If it is desireble to edept the tool to cut threeds on pipe of different diemeters e second guide groove, es 6, 1ney be provided in eech of the ten1plet bers. In the pertiou- 1er oonstruction shown the Pins screw into the sides cf the die oeses end ere introduoed into the groove G through the open freut end thereof.

If it is desired 130 endow the die stook With the cepeoity for eutometioelly moving the dies cleer of the work, efter the required length of threed hes been out, end for holding thern in t-he withdrewn osition until the die cerrier end work holder heving been unscrewed, end of returning then1 to Working position, when the work holder end die cerrier heve been returned 130 the proper relative position for sterting the cutting of e threed, these two g1ooves 6" end 6 n1ey be joined et their upper end lower ends sul stentielly in the menner shown in the dreW- ing, so es to forrn e single endless guide groove. Thet is to sey, there Will be an outwerdly ourving groove 6 formed es e continuetion of ehe lower end of the inner groove 6 end this Will j0in the lower end of the groove 6". There Will also be en inwerdly curving groove 6 es e oontinuetion 0f the upper end of the groove 6 Which Will join the upper end of the groove 6".

lt is oleer thet es the die cerrier is screwed into the work holder With the pins 4l in the grooves 6 seid pins Will trevel down in seid grooves end thereby the dies Will l0e compelled to move, 'or Will be definitely eontrolled in e moven1ent outwerd or in the receding direction. VVhen eech pin reeohes the curved lower end6 of its guide roove, it Will be drewn repidly outwerd, end the dies Will be entirely withdrewn from conteot with the Werk. WVhen ehe die cerrier is now turned in the reverse direction relative t-0 the work holder the pin Will trevel upwerd in the groove 6 end will be held out of possible engegement with the work until the upper curved end 6 of the groove 6 is reeohed. Then the pin 4", es it mo ves in seid groove, Will be moved inwerd end ehe die Will be moved with it until the pin oo1nes over the upper end of ehe groove 6". By now sorewing the die cerrier into the ork holder the pin Will enter the groove 6 end the described operetions Will be repeeted.

In the foregoing desoription perticuler reference hes been only mede to one pin, 130 one templet her end 130 the guide grooves therein, but it Will be understood thet simi- 1er grooves ere for1ned in ell of the ten1plet bers, end thet ell of the dies Will heve ehe seine movemen by reeson of the projection into the grooves 01 the essocieted templet bers of the essocieted pins 4.

Heving thus desoribed my invention, I cleimz l. In e die stock, the comloinetion of e W0rk holder, e die cerrier which is roetively end longitudinelly movelole reletive to the work holder, redielly moveble dies eerried loy the die eerrier, e ring which is rotetebly mounted upon the work holder, but hes 110 longitudinel movernent thereon, templet bers fixed to seid ring end extending longitudinelly forwerd, eeoh templetbei having two perellel inolined guide grooves, e pin rigidly fixed to eech die end edepted to enter either of seid guide grooves, end meens compelling seid ring to rot-ete with seid die cerrier.

2. In e die Stock, the combinetion of e W0rk holder, e die cerrier whioh is rotetively end longitudinelly moveble reletive to the work holder, redielly moveble dies cerried by the die cerrier, e ring which is rotetebly mounted upon the work holder, but bes no longitudinal neovement thereon, templet bers fixed t0 seid ring end extending longitudinelly forwerd, eech heving en endless guidewey which includes two brenches which extend in e generel longitudinal direction side by side,the brench neerest the exis heving its reer end curved ewey from the exis end conneeted with the other brench end t-he brauch ferthest from the exis is et its front end curved towerd the exis end conneoted with the front end of the other brench, e device fixed to eech die engeging seid endless guidewey in the essocieted templet her,

end n1eens cornpelling seid ring 130 rotete wit-h seid die cerrier.

3. In e die stock, the combinetion of e work holder, e die cerrier which is rotetively and longitudinally movable relative to the W0I'k holder, radially movable dies carried by the die carrier, a ring which is rotatably mounted upon the work holder, but has n0 5 longitudinal movement thereon, templetbars fixed t0 said ring and extending longitudinally forward, each templeo bar having two parallel guide grooves of Which the one nearest the axis is curved near its rear end outward and connected with the real: end 0f the other guide groove, und of Which the front end of the guide groove farthest from the axis is curved inward ab its freut end and connected with the front end of the other guide r0ove, a pin rigidly fixed to each die and projecting into seid guide grooves, and means compelling seid ring to rotabe with the die carrier.

In testimony whereof, I hereunto alfix my signature in the presence of two witnesses.

RUSSELL B. TEWKSBURY.

Witnesses:

H. R. SULLIVAN, E. L. THURSTON.

(Jopies of this patent may be obtained tor five cents each, by addressing the Oommissioner 01 Patents, Washington, D. G. 

